Artificial leg



July 23, 1935. w CARNES 2,008,897

ARTIFICIAL LEG Original Filed April 1.4, 1930 2 Sheets$heet 1 3nvcntor914 Z? Ca r1223 Quorum 5 July 23, 1935.

W. T. CARNES ARTIFICIAL LEG Original Filed April 14, 1930 2 Shets-Sheet2 Snuentor Z'Uarrz as.

Patented July 23, 1935 UNITED STATES PATENT OFFICE ARTIFICIAL LEGWilliam T. Carnes, Kansas City, Mo., assignor to Games Artificial LimbCompany, Kansas City, Mo., a corporation of Missouri Originalapplication April 14, 1930, Serial No. 444,067. Divided and thisapplication Novemher a, 1933, Serial'No. 696,554

' Claims.

This invention relates to artificial limbs. One of the objects of theinvention is to produce an artificial limb and foot for amputationsabove the knee, which will enable the wearer to walk I 5 safely and sofreely and naturally as to avoid attures of construction andorganization of parts as hereinafter described and claimed; and in orderthat it may be fully understood, reference is to be had to theaccompanying drawings, in which:

Figure l is a front perspective view of a man wearing an artificial limbfor an amputation ,above the knee, the view also disclosing asimple andefficient harnessforming a part of the invention, for the control of theleg movements in walking and when the wearer seats himself upon orarises from a chair; 1 w I Figure 2 is a perspective view to disclosethe back part of the harness.

Figure 3 is aside view and indicates in dotted lines the position of theartificial limb when the wearer is standing, and as he is starting aforward step with the artificial limb, and also discloses the said limbin a position it may occupy when the wearer is sitting upon a chair.

Figure 4 is. an enlarged central vertical section of the artificial limbat and contiguous to the knee joint thereof. I

Figure5 is a rear view of the same, with the back wall partly brokenaway and the back strap omitted, to more clearly disclose certainelements of the internal mechanism. I I I Figure 6 is a top plan view ofthe lower leg member and the toggle, the front and back straps beingshown in section. I I

I Referring now to the drawings, it will be noted that the lower legportion I is hollow at its upper end and that the sides of such endproject upwardly and engage pivotally with a cross pin 2, extendingtransversely through the lower end of the upper leg portion or socket 3adapted to receive the stump, not shown, ofthe leg; the lower end of theupper leg portion depending into the upper end of the lower leg portionland being rounded so that it may assume aposition at right- I lower legportion l in a plane below and rearward of thepivot pin 2, isa pivot pin4 paralleling I upward and under the left arm and is attached 5.

pivot pin 2, and mounted on said pivot, andpreferably rigid therewith isa toggle, comprising members 5 and 6,the upper end of the latter beingpivoted in the side walls of a channel I in the rear side of the upperleg portion. The lower member is of channel form andreceives 5 the lowerend of member 6, and when the members are alined and the leg isstraight, the channel member prevents the toggle breaking rearwardly.When the wearer is seated the toggle ls collapsed and the lower-memberprojects for- 10 'wardly and the upper member downwardly and forwardly.There is a sound-deadening cushion 8 carried by the lower member toprevent a clicking sound being produced as the expansion of the togglesoccurs through the straightening of the leg. The lower member has aforward 01fset 9 carrying a pin l0 engaged by the front strap of aharness, and also has a rear offset ll coincident with the pivot 4,under which is looped a rear strap of the harness, the lower'end of saidstrap being secured to a pin l2 of said member.

Theharness for-controlling the knee joint action is constructed asfollows: I3 is afront strap which extends around the front side of therounded knee portion diagonally downward and contact with the upper legportion, and a similar .35

roller It carried at the upper end of the lower leg portion, serves as aguide for the rear strap Hi. The front strap l3, at a point on the upperpart of the thigh, runs under one or more guide rolls or keepersv H fora reason which is hereinafter explained, and at a point approximately inthe plane of the waist line is attached toa shoulder loop strap l8 whichextends over the shoulder in line with the artificial limb, the otherend'of said strap being attached to the upper 4:5

end of the strap M, which also extends through a keeper Ha at the backof the upper leg. A second loop l9, extends over the other shoulder andis attached at its lower ends to the'straps' l3 and 4 at the junction ofthe latter with the loop strap [8. I A pair of straps 2H and 2|v arerespectivelyattached at theirlower ends to the front and back straps atthe junctiontherewith of the loops l8'and 19;;Strap20 extends diagonallyat its upper, end to the back portion of the loop l8 near the upper endthereof. Strap 2| extends diagonally upward and forward and also passesunder the left arm and then extends upwardly and forward of the leftshoulder and is attached to the front portion of the loop [8 near thetop thereof.

Referring further to Sheets 1 and 2 of the drawings, it will be notedthat when the artificial leg is straight and the trunk is upright, thestraps l3 and i4 fit against the thigh and the body, and are undersubstantially uniform tension. Now as the wearer starts to step forwardwith the artificial leg by bringing the thigh upward and for- Ward, heleans forward slightly from the hip. This action results in a relaxationof the front strap and the application of increased tension on the backstrap and as a result, the leg bends at the knee in a very naturalmanner and the foot is .lifted, as indicated in the dotted lines b ofFigure 3. He then swings the leg to position a, and straightens thethigh as his body leans back slightly, thus taking up the slack in thefront strap and relaxing the back strap. This action pulls the lower orshank portion ,of the leg in alinement with the thigh portion, and holdsit so until the foot is upon the ground and as long as the tensionremains on the front strap. Assuming the wearer steps forward withtheother foot, he maintains the artificial leg in straight or rigidposition untilthe body is again in a forwardly leaning position and theweight is on both feet, but with the artificial leg still straightenedand in line with the inclination of the body. As the weight istransferred wholly to the right leg, and the body is inclined from thehip still further forward, the front strap is relaxed and the rear strapis tensioned. As this occurs the thigh is lifted, the lower portion ofthe leg is lifted rearwardly, and the leg can be swung forward withsufiicient clearance to avoid ordinary ground obstructions, or ascend astairway. The loop I9 cooperates with the loop l8 in maintaining thefront and rear straps in proper relation to the leg, and the under armstraps 20 and 2| prevents the former from slipping sideways, andprevents slippage of the straps l8and. [9 back and forth on theshoulders, and in this connection, it will be noted by reference toFigure 1, that the guide llis desirable to hold the front strap closelyadjacent the body at the junction of the trunk and thigh, as otherwisewhen the thigh is raised in taking a step or when the wearer occupies asitting position as indicated by dotted lines C, Figure 3, the frontstrap would tend to run direct from the point of the knee to theshoulder and hence bulge the wearers clothing forwardly in a frontstrap. As the wearer arises to his feet and the thigh approaches avertically alined position with his body, a pull is applied on the frontstrap to swing the toggle back to its normal po- I sition and the backstrap is correspondingly slackened. 'In other words, it will beseen'that res traighten the leg.

the back strap performs a pulling operation when the wearer is seatinghimself and that when he is rising from a seated posture, the frontstrap performs the pulling function. When the leg is straight, the lowerend of bar 6 bears against the channel member 6 and thus guards againstthe leg breaking rearwardly or forwardly atthe knee, that is to say, itguards against the lower portion of the leg from swinging forward beyonda position of alinement with the thigh, and also prevents doubling up ofthe leg until an upward pull is applied on the back strap or pressure isotherwise applied to the break-joint portion of the mechanism. When theleg is bent at the knee substantially at right angles, as indicated bythe dotted lines in Figure l, the break-joint brace is in collapsedcondition, the members 5 and 6 thereof extending convergingly forward,and as the leg straightens the angle between the said parts widens untileventually the upper and lower leg members attain an alined position,the member 6 engaging and being arrested by the cushion 8 as suchpositions of the leg members are attained.

From the above description it will be noted that this application formsa division of my application Serial No. 444,067, filed April 14, 1980,and it will be evident that I have produced an artificial leg embodyingthe features of advantage set forth as desirable, and while I havedescribed the preferred embodiment it is to be understood that I reservethe right to all changes within the spirit of the invention and withoutthe ambit of the prior art.

l. The combination of an upper, leg member and a lower leg memberpivoted together, and a toggle pivotally suspended from the upper legmember within the lower leg member, the lower member of said togglehaving an upper extension bearing rearwardly against the upper togglemember when the leg is straightened and withdrawn ,fromsaid upper togglemember when the leg is bent.

2 The combination of an upper leg member and a lower leg member pivotedtogether, a toggle pivotally suspended from theupper leg member withinthe lower leg member, the lower member of said toggle having anupperextension bearing rearwardly against the upper toggle member whenthe leg is straightened and withdrawn from said upper toggle member whenthe leg is bent, a front 'strap'e'xtendingalong the front side of theupper leg member and into the lower leg member and attached to the lowertoggle member; said strap extending diagonally downward and rearwardwithin the lower leg member when the leg is straight, and being engagedwith and bent by the extension of said lower toggle member whenthe legisbent to approximately a right angle, and means for exerting an upwardpull along the front side of the upper leg member to 3. The combinationof ,an upper leg member anda lower leg memberpivoted together, a togglepivotally suspended from the upper leg member within the lower legmember, the lower member of said toggle having an upper extensionbearing rearwardly against the upper toggle member when the leg isstraightened and withdrawn from said upper toggle member when the leg isbent, a rear strap extending along the rear side of the upper leg memberand within the lower leg member and having a looped engagement with thelower endof the lower toggle mer'nber and a fixed engagement at itsextremity with saidtoggle member at an intermediate point thereof, andmeans for exerting an upward pull along the rear side of the upper legmember for bringing the leg from a straight to a bent condition.

4. The combination of an upper leg member and a lower leg member hingedtogether, a toggle pivotally suspended from the upper member back of thehinge point of the leg members, the lower member of the toggle havingfront and rear offset portions 'at its lower end and an eX- tension atits upper end overlapping the lower portion of and adapted to applyrearward pressure against the upper toggle member above the jointbetween the toggle members, when the leg is straightened, and a shoulderstrap loop having its front end extending along the front side of theupper leg member and down into the lower leg member and attached to thefront offset of the lower toggle member, and having its rear endextending along the rear side of the upper leg member and into the lowerleg member and looped forwardly under the rear ofiset of and attached atits end to the lower toggle member at an intermediate point thereof, theextension of said lower toggle member being adapted to engage and bendthe front end of the strap loop when the. two leg members standapproximately at right angles to each other.

5. The combination of an upper leg member and a lower leg member hingedtogether, a toggle pivotally suspended from the upper member back of thehinge point of the leg members, the lower member of the toggle havingfront and rear offset portions at its lower end and an extension at itsupper end overlapping the lower portion of. and adapted to applyrearward pressure against the upper toggle member above the jointbetween the toggle members, when the leg is straightened, and a shoulderstrap loop having its front end extending along the front side of theupper leg member and into the lower leg member and attached to the frontofiset of the lower toggle member, and having its rear end extendingalong the rear side of the upper leg member and into the lower legmember and looped forwardly under the rear offset of and attached at dits end to the lower toggle member at an intermediate point thereof, theextension of said lower toggle member being adapted to engage and bendthe front end of the strap loop when the two leg members standapproximately at right angles to each other.

WILLIAM T. CARNES.

